Tem Characterization of Irradiated U3SI2/AL Dispersion Fuel
Tem Characterization of Irradiated U3SI2/AL Dispersion Fuel

Author:

Publisher:

Published: 2010

Total Pages:

ISBN-13:

DOWNLOAD EBOOK

The silicide dispersion fuel of U3Si2/Al has been recognized as a reasonably good performance fuel for nuclear research and test reactors except that it requires the use of high enrichment uranium. An irradiated U3Si2/Al dispersion fuel (~75% enrichment) from the high flux side of a RERTR-8 (U0R040) plate was characterized using transmission electron microscopy (TEM). The fuel plate was irradiated in the advanced test reactor (ATR) for 105 days. The average irradiation temperature and fission density of the fuel particles for the TEM sample are estimated to be approximately ~110 degrees C and 5.4 x 10-21 f/cm3. The characterization was performed using a 200KV TEM with a LaB6 filament. Detailed microstructural information along with composition analysis is obtained. The results and their implication on the performance of this silicide fuel are discussed.

Results of Recent Microstructural Characterization of Irradiated U-Mo Dispersion Fuels with Al Alloy Matrices that Contain Si
Results of Recent Microstructural Characterization of Irradiated U-Mo Dispersion Fuels with Al Alloy Matrices that Contain Si

Author:

Publisher:

Published: 2008

Total Pages:

ISBN-13:

DOWNLOAD EBOOK

RERTR U-Mo dispersion fuel plates are being developed for application in research reactors throughout the world. As part of this development, reactor experiments are being conducted in the Advanced Test Reactor to determine the irradiation performance of different dispersion fuels that contain U-Mo alloys with different Mo contents and Al alloy matrices with different Si contents. Of particular interest is the performance of the dispersion fuels depending on the Si content of the Al alloy matrix, since the addition of Si is being looked to for improving the performance of these dispersion fuels. This paper will describe the results of recent microstructural examinations that have been performed using optical metallography and scanning electron microscopy on as-fabricated and as-irradiated dispersion fuels with different amounts of Si added to the Al matrix. Differences in the microstructural development during irradiation as a function of the Si content in the Al matrix will be discussed, and comments will be made about the development and stability of the fuel/matrix interaction layers that are commonly present in irradiated dispersion fuels.

Characterization of the Microstructure of Irradiated U-Mo Dispersion Fuel with a Matrix that Contains Si
Characterization of the Microstructure of Irradiated U-Mo Dispersion Fuel with a Matrix that Contains Si

Author:

Publisher:

Published: 2009

Total Pages:

ISBN-13:

DOWNLOAD EBOOK

RERTR U-Mo dispersion fuel plates are being developed for application in research reactors throughout the world. Of particular interest is the irradiation performance of U-Mo dispersion fuels with Si added to the Al matrix. Si is added to improve the performance of U-Mo dispersion fuels. Microstructural examinations have been performed on fuel plates with Al-2Si matrix after irradiation to around 50% LEU burnup. Si-rich layers were observed in many areas around the various U-7Mo fuel particles. In one local area of one of the samples, where the Si-rich layer had developed into a layer devoid of Si, relatively large fission gas bubbles were observed in the interaction phase. There may be a connection between the growth of these bubbles and the amount of Si present in the interaction layer. Overall, it was found that having Si-rich layers around the fuel particles after fuel plate fabrication positively impacted the overall performance of the fuel plate.

Comparison of Irradiation Behavior of Different Uranium Silicide Dispersion Fuel Element Designs
Comparison of Irradiation Behavior of Different Uranium Silicide Dispersion Fuel Element Designs

Author:

Publisher:

Published: 1995

Total Pages: 12

ISBN-13:

DOWNLOAD EBOOK

Calculations of fuel swelling of U3SiAl-Al and U3Si2 were performed for various dispersion fuel element designs. Breakaway swelling criteria in the form of critical fuel volume fractions were derived with data obtained from U3SiAl-Al plate irradiations. The results of the analysis show that rod-type elements remain well below the pillowing threshold. However, tubular fuel elements, which behave essentially like plates, will likely develop pillows or blisters at around 90% 235U burnup. The U3Si2-Al compounds demonstrate stable swelling behavior throughout the entire burnup range for all fuel element designs.

Postirradiation Examination of a Low Enriched U3Si2-Al Fuel Element Manufactured and Irradiated at Batan, Indonesia
Postirradiation Examination of a Low Enriched U3Si2-Al Fuel Element Manufactured and Irradiated at Batan, Indonesia

Author:

Publisher:

Published: 1994

Total Pages: 9

ISBN-13:

DOWNLOAD EBOOK

The first low-enriched U3Si2-Al dispersion plate-type fuel element produced at the Nuclear Fuel Element Center, BATAN, Indonesia, was irradiated to a peak 235U burnup of 62%. Postirradiation examinations performed to data shows the irradiation behavior of this element to be similar to that of U3Si2-Al plate-type fuel produced and tested at other institutions. The main effect of irradiation on the fuel plates is a thickness increase of 30--40 [mu]m (2.5-3.0%). This thickness increase is almost entirely due to the formation of a corrosion layer (Boehmite). The contribution of fuel swelling to the thickness increase is rather small (less than 10 [mu]m) commensurate with the burnup of the fuel and the relatively moderate as-fabricated fuel volume fraction of 27% in the fuel meat.

Post-irradiation Examination of U3Si{sub 1.6}-Al Dispersion Fuel Element LC04
Post-irradiation Examination of U3Si{sub 1.6}-Al Dispersion Fuel Element LC04

Author:

Publisher:

Published: 1993

Total Pages: 16

ISBN-13:

DOWNLOAD EBOOK

A low-enrichment uranium (LEU) irradiation test (SIMONE project) was performed in the 45 MW Petten High-flux Reactor (HFR) as part of the Reduced Enrichment for Research and Test Reactor (RERTR) program. An LEU U3Si{sub 1.6}-Al dispersion fuel element with a fuel loading of 5.5 g cm−3 was irradiated and performed well to a total burnup of 66% and a peak burnup of 85%. The swelling behavior of the fuel was similar to that observed in previous U3Si(subscript x) irradiation experiments. The resulting fuel plate thickness increases and associated changes in coolant channel cross-sections were well within acceptable limits.

Detailed Analysis of Uranium Silicide Dispersion Fuel Swelling
Detailed Analysis of Uranium Silicide Dispersion Fuel Swelling

Author:

Publisher:

Published: 1989

Total Pages: 21

ISBN-13:

DOWNLOAD EBOOK

Swelling of U3Si and U3Si2 is analyzed. The growth of fission gas bubbles appears to be affected by fission rate, fuel loading, and microstructural change taking place in the fuel compounds during irradiation. Several mechanisms are explored to explain the observations. The present work is aimed at a better understanding of the basic swelling phenomenon in order to accurately model irradiation behavior of uranium silicide disperson fuel. 5 refs., 10 figs.

Predicted Irradiation Behavior of U Sub 3 O Sub 8 -Al Dispersion Fuels for Production Reactor Applications
Predicted Irradiation Behavior of U Sub 3 O Sub 8 -Al Dispersion Fuels for Production Reactor Applications

Author:

Publisher:

Published: 1990

Total Pages: 7

ISBN-13:

DOWNLOAD EBOOK

Candidate fuels for the new heavy-water production reactor include uranium/aluminum alloy and U3O--Al dispersion fuels. The U3O--Al dispersion fuel would make possible higher uranium loadings and would facilitate uranium recycle. Research efforts on U3O8--Al fuel include in-pile irradiation studies and development of analytical tools to characterize the behavior of dispersion fuels at high-burnup. In this paper the irradiation performance of U3O8--Al is assessed using the mechanistic Dispersion Analysis Research Tool (DART) code. Predictions of fuel swelling and alteration of thermal conductivity are presented and compared with experimental data. Calculational results indicate good agreement with available data where the effects of as-fabricated porosity and U3O8--Al oxygen exchange reactions are shown to exert a controlling influence on irradiation behavior. The DART code is judged to be a useful tool for assessing U3O8--Al performance over a wide range of irradiation conditions. 8 refs., 8 figs., 1 tab.

Thermal Conductivities of U3Si and U3Si2-Al Dispersion Fuels
Thermal Conductivities of U3Si and U3Si2-Al Dispersion Fuels

Author:

Publisher:

Published: 1985

Total Pages:

ISBN-13:

DOWNLOAD EBOOK

Two high density uranium silicides are being evaluated as replacements for the research reactor fuels currently in use. Employing these compounds permits a major reduction in uranium enrichment, and tests have shown that the silicide fuels perform well under irradiation. Thermal conductivity data are required for analysis of these results and for safety calculations. The data show that silicide-Al dispersion fuels have somewhat better thermal conductivities than U3O-Al dispersions, but their principal advantage is in their increased uranium content. The differences between the thermal conductivities of U3Si and U3Si2 dispersions are small, but the microstructure of the dispersion was found to have a major influence on thermal conductivity. This seems to be associated with the formation of planar porosity defects during the roll bonding process, and differences as large as a factor of four (59 vs. 14 W/m . K) were noted for the samples having equal U3Si2 contents (46 v/o).